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A new transmission strategy based on distributed event-triggered mechanism and average dwell time approach is proposed for consensus of time-delay free linear multi-agent systems with communication constraints. A subset of agents are selected according to the condition of event-triggered mechanism to communicate with its adjacent agents through network channel at certain sampling instant, which reduces the occupation of network bandwidth. The possible combinations of agents' communication are considered as modes of multi-agent systems. Therefore, we modelled multi-agent systems as a class of switched systems. The average dwell time method is applied to determine its dwell-time of each mode, which avoids the frequent mode-switching resulted from event-triggered mechanism. An integrated design scheme is presented to achieve the thresholds of event-triggered mechanism, the average dwell time and the consensus controller gain simultaneously by using Lyapunov–Krasovskii functional and linear matrix inequality (LMI) technique. Finally, a simulation example illustrates the effectiveness of theoretical results. [ABSTRACT FROM AUTHOR]

Background Infection prevention techniques used during cerebrospinal fluid (CSF) shunt surgery include: (1) standard perioperative intravenous antibiotics, (2) intrathecal (IT) antibiotics, (3) antibiotic-impregnated catheter (AIC) shunt tubing, or (4) Both IT and AIC. These techniques have not been assessed against one another for their impact on the infecting organisms and patterns of antimicrobial resistance. Methods We performed a retrospective longitudinal observational cohort study of children with initial CSF shunt placement between January 2007 and December 2012 at 6 US hospitals. Data were collected electronically from the Pediatric Health Information Systems+ (PHIS+) database, and augmented with standardized chart review. Only subjects with positive CSF cultures were included in this study. Results Of 1,723 children whose initial shunt placement occurred during the study period, 196 (11%) developed infection, with 157 (80%) having positive CSF cultures. Of these 157 subjects, 69 (44%) received standard care, 28 (18%) received AIC, 55 (35%) received IT antibiotics, and 5 (3%) received Both at the preceding surgery. The most common organisms involved in monomicrobial infections were Staphylococcus aureus (38, 24%), coagulase-negative staphylococci (36, 23%), and Cutibacterium acnes (6, 4%). Compared with standard care, the other infection prevention techniques were not significantly associated with changes to infecting organisms; AIC was associated with decreased odds of methicillin resistance among coagulase-negative staphylococci. Conclusions Because no association was found between infection prevention technique and infecting organisms when compared to standard care, other considerations such as tolerability, availability, and cost should inform decisions about infection prevention during CSF shunt placement surgery. [ABSTRACT FROM AUTHOR]

Plant cells are totipotent and competent to regenerate from differentiated organs. It has been known for six decades that cytokinin-rich medium induces shoot regeneration from callus cells. However, the underlying molecular mechanism remains elusive. The homeodomain transcription factor WUSCHEL (WUS) is essential for de novo establishment of the shoot stem cell niche in Arabidopsis thaliana. We found that WUS-positive (WUS+) cells mark the shoot progenitor region during regeneration. A cytokinin-rich environment initially promotes the removal of the repressive histone mark H3K27me3 at the WUS locus in a cell cycle-dependent manner. Subsequently, the B-type ARABIDOPSIS RESPONSE REGULATORs (ARRs) ARR1, ARR2, ARR10, and ARR12, which function as transcriptional activators in the cytokinin signaling pathway, spatially activate WUS expression through binding with microRNA165/6-targeted HD-ZIP III transcription factors. Thus, our results provide important insights into the molecular framework for cytokinin-directed shoot regeneration and reveal a two-step mechanism for de novo activation of WUS. [ABSTRACT FROM AUTHOR]

Objective Pain-related function is not routinely assessed in the hospital. This prospective cohort study examined whether patients' daily pain-related function during hospitalization, based on the validated Youth Acute Pain Functional Ability Questionnaire (YAPFAQ), is associated with pain and quality of life. Design The YAPFAQ is a 12-item measure assessing functional parameters of recovery related to pain and has been validated in children and adolescents with sickle cell disease and after surgery. Adolescents undergoing major musculoskeletal surgery (n = 93) completed the YAPFAQ daily for up to 3 days after surgery. Adolescents self-reported health-related quality of life on the Pediatric Quality of Life Inventory and pain intensity on a numeric rating scale at home 2 weeks after surgery. Results Higher YAPFAQ scores, representing poorer function, were associated with higher pain intensity (β = 0.2, P  = 0.04) and poorer health-related quality of life (β   =   –0.3, P  = 0.01) at home 2 weeks after surgery. This functional measure could be clinically relevant to providers to identify adolescents at risk of difficulty with pain and recovery at home after surgery who might need further intervention to minimize functional impairment and delayed recovery. Perspective This article provides conceptual validation of a functional score for pediatric pain, the YAPFAQ, to assess pain intensity and health-related quality of life in the subacute period. [ABSTRACT FROM AUTHOR]

Background This study was designed to determine whether an automated hospital-based influenza vaccination screening program leveraging the electronic medical record (EMR) increases vaccination rates. Methods We performed a retrospective cohort study of all children ≥6 months old admitted to medical, surgical, rehabilitation, or psychiatry services during influenza seasons between 2003 and 2012 at a tertiary care pediatric hospital. We compared influenza vaccination rates before (preintervention phase) and after (intervention phase) the introduction of an automated EMR intervention that utilized a nursing-based electronic screening tool to determine eligibility for influenza vaccine and facilitated vaccine ordering without requiring involvement of a physician or other provider. Results Overall, 42 716 (72.8%) of the 58,648 subjects admitted during the study period met inclusion criteria. The intervention phase included 20,651 admissions, of which 11 194 (54.2%) were screened. Screening increased significantly over time in the intervention phase (19.8%–77.1%; P < .001). In-hospital influenza vaccination rates increased from a mean of 2.1% (n = 472) of all subjects preintervention phase to 8.0% (n = 1645) in the intervention phase (odds ratio = 6.8; 95% confidence interval, 6.14–7.47). Of the 11 194 screened subjects, 5505 (49.2%) were found to have already been vaccinated at the time of screening. The screening process identified 478 (4.3%) subjects who were unable to receive vaccine for medical reasons, and an additional 2865 (25.6%) whose caregiver refused the vaccine. Conclusions An automated, hospital-based influenza vaccination program integrated into the EMR can increase vaccinations of hospitalized patients and provide insight into the vaccination history and declination reasons for children not receiving the vaccine. [ABSTRACT FROM PUBLISHER]

Motivation: We present an integrated toolkit, BoBro2.0, for prediction and analysis of cis-regulatory motifs. This toolkit can (i) reliably identify statistically significant cis-regulatory motifs at a genome scale; (ii) accurately scan for all motif instances of a query motif in specified genomic regions using a novel method for P-value estimation; (iii) provide highly reliable comparisons and clustering of identified motifs, which takes into consideration the weak signals from the flanking regions of the motifs; and (iv) analyze co-occurring motifs in the regulatory regions.Results: We have carried out systematic comparisons between motif predictions using BoBro2.0 and the MEME package. The comparison results on Escherichia coli K12 genome and the human genome show that BoBro2.0 can identify the statistically significant motifs at a genome scale more efficiently, identify motif instances more accurately and get more reliable motif clusters than MEME. In addition, BoBro2.0 provides correlational analyses among the identified motifs to facilitate the inference of joint regulation relationships of transcription factors.Availability: The source code of the program is freely available for noncommercial uses at http://code.google.com/p/bobro/.Contact: xyn@bmb.uga.eduSupplementary information: Supplementary data are available at Bioinformatics online. [ABSTRACT FROM PUBLISHER]

Corpse management is essential for social animals to maintain colony health. In the eastern subterranean termite, Reticulitermes flavipes, workers carry out undertaking behaviors to mitigate the risks associated with the dead. In this study, we hypothesized that termites would respond differently to the corpses from different castes based on their postmortem chemical signatures. To test this hypothesis, we 1) documented the behavioral responses of the workers toward corpses from different castes, and 2) profile the chemical signatures of these corpses. Corpses from all castes were retrieved inside the nests and cannibalized when they were decomposed <64 h, regardless of the presence or absence of the cues that we refer to as early death cues (3-octanol and 3-octanone). However, after 64 h, all corpses except for soldiers were buried on site by R. flavipes workers. The late death cues (oleic acid) were cumulative over time among castes but accumulated more slowly and at lower levels in soldiers. The differential release of 3-octanol and 3-octanone between workers/soldiers and nymphs could be explained by either qualitative or quantitative differences in signaling the death between imaginal and neuter developmental pathways. In summary, the efficient and selective recognition of the dead and the fine-tuning of subsequent undertaking responses observed in R. flavipes are aspects of corpse management, which can minimize the potential risks associated with different castes and maximize the colony fitness. [ABSTRACT FROM AUTHOR]

Age and wounding are two major determinants for regeneration. In plants, the root regeneration is triggered by wound-induced auxin biosynthesis. As plants age, the root regenerative capacity gradually decreases. How wounding leads to the auxin burst and how age and wound signals collaboratively regulate root regenerative capacity are poorly understood. Here, we show that the increased levels of three closely-related miR156-targeted Arabidopsis (Arabidopsis thaliana) SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors, SPL2, SPL10, and SPL11, suppress root regeneration with age by inhibiting wound-induced auxin biosynthesis. Mechanistically, we find that a subset of APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factors including ABSCISIC ACID REPRESSOR1 and ERF109 is rapidly induced by wounding and serves as a proxy for wound signal to induce auxin biosynthesis. In older plants, SPL2/10/11 directly bind to the promoters of AP2 / ERFs and attenuates their induction, thereby dampening auxin accumulation at the wound. Our results thus identify AP2/ERFs as a hub for integration of age and wound signal for root regeneration. [ABSTRACT FROM AUTHOR]

Plant cells are totipotent and competent to regenerate from differentiated organs. It has been shown that two phytohormones, auxin and cytokinin, play critical roles within this process. As in animals, the regenerative capacity declines with age in plants, but the molecular basis for this phenomenon remains elusive. Here, we demonstrate that an age-regulated microRNA, miR156, regulates shoot regenerative capacity. As a plant ages, the gradual increase in miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factors leads to the progressive decline in shoot regenerative capacity. In old plants, SPL reduces shoot regenerative capacity by attenuating the cytokinin response through binding with the B-type ARABIDOPSIS RESPONSE REGULATORs, which encode the transcriptional activators in the cytokinin signaling pathway. Consistently, the increased amount of exogenous cytokinin complements the reduced shoot regenerative capacity in old plants. Therefore, the recruitment of age cues in response to cytokinin contributes to shoot regenerative competence. [ABSTRACT FROM AUTHOR]